Remove BrowserThread-specific implementation of MessageLoopProxy.

content/public/browser/browser_thread.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CONTENT_PUBLIC_BROWSER_BROWSER_THREAD_H_
 #define CONTENT_PUBLIC_BROWSER_BROWSER_THREAD_H_
 #pragma once
 
 #include <string>
 
@@ skipping 133 matching lines @@
     scoped_refptr<base::MessageLoopProxy> message_loop_proxy =
         GetMessageLoopProxyForThread(identifier);
     return base::PostTaskAndReplyWithResult<ReturnType>(
         message_loop_proxy.get(), from_here, task, reply);
   }
 
   template <class T>
   static bool DeleteSoon(ID identifier,
                          const tracked_objects::Location& from_here,
                          const T* object) {
-    return GetMessageLoopProxyForThread(identifier)->DeleteSoon(
-        from_here, object);
+    scoped_refptr<base::MessageLoopProxy> message_loop_proxy =
+        GetMessageLoopProxyForThread(identifier);
+    if (!message_loop_proxy)
+      return false;
+    return message_loop_proxy->DeleteSoon(from_here, object);
   }
 
   template <class T>
   static bool ReleaseSoon(ID identifier,
                           const tracked_objects::Location& from_here,
                           const T* object) {
     return GetMessageLoopProxyForThread(identifier)->ReleaseSoon(
         from_here, object);
   }
 
@@ skipping 117 matching lines @@
  private:
   friend class BrowserThreadImpl;
 
   BrowserThread() {}
   DISALLOW_COPY_AND_ASSIGN(BrowserThread);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_PUBLIC_BROWSER_BROWSER_THREAD_H_